A phase I study of pevonedistat, azacitidine, and venetoclax in patients with relapsed/refractory acute myeloid leukemia.

Azacitidine/venetoclax is an active regimen in patients with newly diagnosed AML. However, primary or secondary resistance to azacitidine/venetoclax is an area of unmet need and overexpression of MCL-1 is suggested to be a potential resistance mechanism. Pevonedistat inhibits MCL-1 through activation of NOXA, and pevonedistat/azacitidine has previously shown activity in AML. To assess the tolerability and efficacy of adding pevonedistat to azacitidine/venetoclax in relapsed/refractory AML, we conducted a phase I multicenter openlabel study in 16 adults with relapsed/refractory AML. Patients were treated with azacitidine, venetoclax along with pevonedistat intravenously on days 1, 3 and 5 of each 28-day cycle at 10, 15 or 20 mg/m2 in successive cohorts in the dose escalation phase. The impact of treatment on protein neddylation as well as expression of pro-apoptotic BCL2 family members was assessed. The recommended phase II dose of pevonedistat was 20 mg/m2. Grade 3 or higher adverse events included neutropenia (31%), thrombocytopenia (13%), febrile neutropenia (19%), anemia (19%), hypertension (19%) and sepsis (19%). The overall response rate was 46.7% for the whole cohort including complete remission (CR) in 5 of 7 (71.4%) patients who were naïve to the hypomethylating agent/venetoclax. No measurable residual disease (MRD) was detected in 80.0% of the patients who achieved CR. The median time to best response was 50 (range: 23 - 77) days. Four patients were bridged to allogeneic stem cell transplantation. The combination of azacitidine, venetoclax and pevonedistat is safe and shows encouraging preliminary activity in patients with relapsed/refractory AML. (NCT04172844).

Single-cell systems pharmacology identifies development-driven drug response and combination therapy in B cell acute lymphoblastic leukemia.

Leukemia can arise at various stages of the hematopoietic differentiation hierarchy, but the impact of developmental arrest on drug sensitivity is unclear. Applying network-based analyses to single-cell transcriptomes of human B cells, we define genome-wide signaling circuitry for each B cell differentiation stage. Using this reference, we comprehensively map the developmental states of B cell acute lymphoblastic leukemia (B-ALL), revealing its strong correlation with sensitivity to asparaginase, a commonly used chemotherapeutic agent. Single-cell multi-omics analyses of primary B-ALL blasts reveal marked intra-leukemia heterogeneity in asparaginase response: resistance is linked to pre-pro-B-like cells, with sensitivity associated with the pro-B-like population. By targeting BCL2, a driver within the pre-pro-B-like cell signaling network, we find that venetoclax significantly potentiates asparaginase efficacy in vitro and in vivo. These findings demonstrate a single-cell systems pharmacology framework to predict effective combination therapies based on intra-leukemia heterogeneity in developmental state, with potentially broad applications beyond B-ALL.

Cladribine plus cytarabine plus venetoclax in acute myeloid leukemia relapsed or refractory to venetoclax plus hypomethylating agent.

Not available.

Prognostic impact of SF3B1 mutation and multilineage dysplasia in myelodysplastic syndromes with ring sideroblasts: a Mayo Clinic study of 170 informative cases.

The revised 4th edition of the World Health Organization (WHO4R) classification lists myelodysplastic syndromes with ring sideroblasts (MDS-RS) as a separate entity with single lineage (MDS-RS-SLD) or multilineage (MDS-RS-MLD) dysplasia. The more recent International Consensus Classification (ICC) distinguishes between MDS with SF3B1 mutation (MDS-SF3B1) and MDS-RS without SF3B1 mutation; the latter is instead included under the category of MDS not otherwise specified. The current study includes 170 Mayo Clinic patients with WHO4R-defined MDS-RS, including MDS-RS-SLD (N=83) and MDS-RS-MLD (N=87); a subset of 145 patients were also evaluable for the presence of SF3B1 and other mutations, including 126 with (87%) and 19 (13%) without SF3B1 mutation. Median overall survival for all 170 patients was 6.6 years with 5- and 10-year survival rates of 59% and 25%, respectively. A significant difference in overall survival was apparent between MDS-RS-MLD and MDS-RS-SLD (p<0.01) but not between MDS-RS with and without SF3B1 mutation (p=0.36). Multivariable analysis confirmed the independent prognostic contribution of MLD (HR 1.8, 95% CI 1.1-2.8; p=0.01) and also identified age (p<0.01), transfusion need at diagnosis (p<0.01), and abnormal karyotype (p<0.01), as additional risk factors; the impact from SF3B1 or other mutations was not significant. Leukemia-free survival was independently affected by abnormal karyotype (p<0.01), RUNX1 (0.02) and IDH1 (p=0.01) mutations, but not by MLD or SF3B1 mutation. Exclusion of patients not meeting ICC-criteria for MDSSF3B1 did not change the observations on overall survival. MLD-based, as opposed to SF3B1 mutationbased, disease classification for MDS-RS might be prognostically more relevant.

Gilteritinib as Post-Transplant Maintenance for Acute Myeloid Leukemia With Internal Tandem Duplication Mutation of FLT3.

PURPOSE: Allogeneic hematopoietic cell transplantation (HCT) improves outcomes for patients with acute myeloid leukemia (AML) harboring an internal tandem duplication mutation of FLT3 (FLT3-ITD) AML. These patients are routinely treated with a FLT3 inhibitor after HCT, but there is limited evidence to support this. Accordingly, we conducted a randomized trial of post-HCT maintenance with the FLT3 inhibitor gilteritinib (ClinicalTrials.gov identifier: NCT02997202) to determine if all such patients benefit or if detection of measurable residual disease (MRD) could identify those who might benefit. METHODS: Adults with FLT3-ITD AML in first remission underwent HCT and were randomly assigned to placebo or 120 mg once daily gilteritinib for 24 months after HCT. The primary end point was relapse-free survival (RFS). Secondary end points included overall survival (OS) and the effect of MRD pre- and post-HCT on RFS and OS. RESULTS: Three hundred fifty-six participants were randomly assigned post-HCT to receive gilteritinib or placebo. Although RFS was higher in the gilteritinib arm, the difference was not statistically significant (hazard ratio [HR], 0.679 [95% CI, 0.459 to 1.005]; two-sided P = .0518). However, 50.5% of participants had MRD detectable pre- or post-HCT, and, in a prespecified subgroup analysis, gilteritinib was beneficial in this population (HR, 0.515 [95% CI, 0.316 to 0.838]; P = .0065). Those without detectable MRD showed no benefit (HR, 1.213 [95% CI, 0.616 to 2.387]; P = .575). CONCLUSION: Although the overall improvement in RFS was not statistically significant, RFS was higher for participants with detectable FLT3-ITD MRD pre- or post-HCT who received gilteritinib treatment. To our knowledge, these data are among the first to support the effectiveness of MRD-based post-HCT therapy.

Cardiac events in newly diagnosed acute myeloid leukaemia during treatment with venetoclax + hypomethylating agents.

Among 301 newly diagnosed patients with acute myeloid leukaemia receiving venetoclax and a hypomethylating agent, 23 (7.6%) experienced major cardiac complications: 15 cardiomyopathy, 5 non-ST elevation myocardial infarction and/or 7 pericarditis/effusions. Four patients had more than one cardiac complication. Baseline characteristics included median age ± interquartile range; 73 ± 5 years; 87% males; 96% with cardiovascular risk factors; and 90% with preserved baseline ejection fraction. In multivariate analysis, males were more likely (p = 0.02) and DNMT3A-mutated cases less likely (p < 0.01) to be affected. Treatment-emergent cardiac events were associated with a trend towards lower composite remission rates (43% vs. 62%; p = 0.09) and shorter survival (median 7.7 vs. 13.2 months; p < 0.01). These observations were retrospectively retrieved and warrant further prospective examination.

Clinical outcomes of hypomethylating agents plus Venetoclax as frontline treatment in patients 75 years and older with acute myeloid leukemia: Real-world data from eight US academic centers.

Venetoclax (VEN) combined with hypomethylating agents (HMAs) is the standard of care for the treatment of patients with newly diagnosed acute myeloid leukemia (AML) unfit for intensive chemotherapy. To date, real-world data published on HMAs plus VEN have been either single-center studies or using community-based electronic databases with limited details on mutational landscape, tolerability, and treatment patterns in elderly patients. Therefore, we conducted a multicenter retrospective study to assess the real-world experience of 204 elderly patients (≥75 years) with newly diagnosed AML treated with HMAs plus VEN from eight academic centers in the United States. Overall, 64 patients achieved complete remission (CR; 38%) and 43 CR with incomplete count recovery (CRi; 26%) for a CR/CRi rate of 64%, with a median duration of response of 14.2 months (95% CI: 9.43, 22.1). Among responders, 63 patients relapsed (59%) with median overall survival (OS) after relapse of 3.4 months (95% CI, 2.4, 6.7). Median OS for the entire population was 9.5 months (95% CI, 7.85-13.5), with OS significantly worse among patients with TP53-mutated AML (2.5 months) and improved in patients harboring NPM1, IDH1, and IDH2 mutations (13.5, 18.3, and 21.1 months, respectively). The 30-day and 60-day mortality rates were 9% and 19%, respectively. In conclusion, HMAs plus VEN yielded high response rates in elderly patients with newly diagnosed AML. The median OS was inferior to that reported in the VIALE-A trial. Outcomes are dismal after failure of HMAs plus VEN, representing an area of urgent unmet clinical need.

Genetic landscape and clinical outcomes of patients with BCOR mutated myeloid neoplasms.

The BCL6-corepressor (BCOR) is a tumor-suppressor gene located on the short arm of chromosome X. Data is limited regarding factors predicting survival in BCOR-mutated (mBCOR) acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). We evaluated 138 patients with mBCOR myeloid disorders, of which 36 (26.1%) had AML and 63 (45.6%) had MDS. Sixty-six (47.8%) patients had a normal karyotype while 18 (13%) patients had complex karyotype. BCOR-mutated MDS/AML were highly associated with RUNX1 and U2AF1 comutations. In contrast, TP53 mutation was infrequently seen with mBCOR MDS. Patients with an isolated BCOR mutation had similar survival compared to those with high-risk co-mutations by ELN 2022 criteria (median OS 1.16 vs. 1.27 years, P = 0.46). Complex karyotype adversely impacted survival among mBCOR AML/MDS (HR 4.12, P < 0.001), while allogeneic stem cell transplant (alloSCT) improved survival (HR 0.38, P = 0.04). However, RUNX1 co-mutation was associated with an increased risk of post-alloSCT relapse (HR 88.0, P = 0.02), whereas melphalan-based conditioning was associated with a decreased relapse-risk (HR 0.02, P = 0.01). We conclude that mBCOR is a high-risk feature across MDS/AML and that alloSCT improves survival in this population.

Follow-up from the A041202 study shows continued efficacy of ibrutinib regimens for older adults with CLL.

ABSTRACT: A041202 (NCT01886872) is a phase 3 study comparing bendamustine plus rituximab (BR) with ibrutinib and the combination of ibrutinib plus rituximab (IR) in previously untreated older patients with chronic lymphocytic leukemia (CLL). The initial results showed that ibrutinib-containing regimens had superior progression-free survival (PFS) and rituximab did not add additional benefits. Here we present an updated analysis. With a median follow-up of 55 months, the median PFS was 44 months (95% confidence interval [CI], 38-54) for BR and not yet reached in either ibrutinib-containing arm. The 48-month PFS estimates were 47%, 76%, and 76% for BR, ibrutinib, and IR, respectively. The benefit of ibrutinib regimens over chemoimmunotherapy was consistent across subgroups of patients defined by TP53 abnormalities, del(11q), complex karyotype, and immunoglobulin heavy chain variable region (IGHV). No significant interaction effects were observed between the treatment arm and del(11q), the complex karyotype, or IGHV. However, a greater difference in PFS was observed among the patients with TP53 abnormalities. There was no difference in the overall survival. Notable adverse events with ibrutinib included atrial fibrillation (afib) and hypertension. Afib was observed in 11 patients (pts) on BR (3%) and 67 pts on ibrutinib (18%). All-grade hypertension was observed in 95 pts on BR (27%) and 263 pts on ibrutinib (55%). These data show that ibrutinib regimens prolong PFS compared with BR for older patients with treatment-naïve CLL. These benefits were observed across subgroups, including high-risk groups. Strikingly, within the ibrutinib arms, there was no inferior PFS for patients with abnormalities in TP53, the highest risk feature observed in CLL. These data continue to demonstrate the efficacy of ibrutinib in treatment-naïve CLL.

Temporal trends in critical care utilization and outcomes in allogeneic hematopoietic stem cell transplant recipients.

Historically, the prognosis of allogeneic hematopoietic stem cell transplant (allo-HCT) recipients who require intensive care unit (ICU) admission has been poor. We aimed to describe the epidemiological trends of ICU utilization and outcomes in allo-HCT patients. We conducted a retrospective cohort study including adults (≥ 18) undergoing allo-HCT between 01/01/2005 and 31/12/2020 at Mayo Clinic, Rochester. Temporal trends in outcomes were assessed by robust linear regression modelling. Risk factors for hospital mortality were chosen a priori and assessed with multivariable logistic regression modelling. Of 1,249 subjects, there were 486 ICU admissions among 287 individuals. Although older patients underwent allo-HCT (1.64 [95% CI: 1.11 to 2.45] years per year; P = 0.025), there was no change in ICU utilization over time (P = 0.91). The ICU and hospital mortality rates were 19.2% (55/287) and 28.2% (81/287), respectively. There was a decline in ICU mortality (-0.38% [95% CI: -0.70 to -0.06%] per year; P = 0.035). The 1-year post-HCT mortality for those requiring ICU admission was 56.1% (161/287), with no significant difference over time, versus 15.8% (141/891, 71 missing) among those who did not. The frequency and duration of invasive mechanical ventilation (IMV) declined. In multivariable analyses, higher serum lactate, higher sequential organ failure assessment (SOFA) scores, acute respiratory distress (ARDS), and need for IMV were associated with greater odds of hospital mortality. Over time, rates of ICU utilization have remained stable, despite increasing patient age. Several trends suggest improvement in outcomes, notably lower ICU mortality and frequency of IMV. However, long-term survival remains unchanged. Further work is needed to improve long-term outcomes in this population.

Venetoclax plus hypomethylating agents in DDX41-mutated acute myeloid leukaemia and myelodysplastic syndrome: Mayo Clinic series on 12 patients.

Venetoclax (VEN) is an FDA-approved selective inhibitor of B-cell leukaemia/lymphoma-2 (BCL-2), used for treating elderly or unfit acute myeloid leukaemia (AML) patients unable to undergo intensive chemotherapy. Combining VEN with hypomethylating agents (HMAs) has shown impressive response rates in high-risk myelodysplastic syndromes (MDS) and relapsed/refractory AML. However, the efficacy of VEN and HMAs in treating DDX41-mutated (mDDX41) MDS/AML patients remains uncertain. Despite the favourable prognostic nature of mDDX41 MDS/AML patients, there is a lack of clinical experience regarding their response to different treatment regimens, leading to an unknown optimal therapeutic approach.

A study to assess the efficacy of enasidenib and risk-adapted addition of azacitidine in newly diagnosed IDH2-mutant AML.

ABSTRACT: Enasidenib (ENA) is an inhibitor of isocitrate dehydrogenase 2 (IDH2) approved for the treatment of patients with IDH2-mutant relapsed/refractory acute myeloid leukemia (AML). In this phase 2/1b Beat AML substudy, we applied a risk-adapted approach to assess the efficacy of ENA monotherapy for patients aged ≥60 years with newly diagnosed IDH2-mutant AML in whom genomic profiling demonstrated that mutant IDH2 was in the dominant leukemic clone. Patients for whom ENA monotherapy did not induce a complete remission (CR) or CR with incomplete blood count recovery (CRi) enrolled in a phase 1b cohort with the addition of azacitidine. The phase 2 portion assessing the overall response to ENA alone demonstrated efficacy, with a composite complete response (cCR) rate (CR/CRi) of 46% in 60 evaluable patients. Seventeen patients subsequently transitioned to phase 1b combination therapy, with a cCR rate of 41% and 1 dose-limiting toxicity. Correlative studies highlight mechanisms of clonal elimination with differentiation therapy as well as therapeutic resistance. This study demonstrates both efficacy of ENA monotherapy in the upfront setting and feasibility and applicability of a risk-adapted approach to the upfront treatment of IDH2-mutant AML. This trial is registered at www.clinicaltrials.gov as #NCT03013998.

A randomized phase III study of standard versus high-dose cytarabine with or without vorinostat for AML.

Prior experience indicated that use of higher doses of cytarabine during induction for acute myeloid leukemia (AML) with a histone deacetylase inhibitor resulted in high response rates. S1203 was a randomized multicenter trial for previously untreated patients aged 18-60 with AML which compared daunorubicin and cytarabine (DA), idarubicin with higher dose cytarabine (IA) and IA with vorinostat (IA + V). The primary endpoint was event free survival (EFS). 738 patients were randomized: 261 to each DA and IA arms and 216 to the IA + V arm. 96, 456, and 150 patients had favorable-, intermediate-, and unfavorable-risk cytogenetics, respectively. 152 were NPM1 and 158 FLT3 mutated. The overall remission rate was 77.5% including 62.5% CR and 15.0% CRi. No differences in remission, EFS, or overall survival were observed among the 3 arms except for the favorable cytogenetics subset who had improved outcomes with DA and postremission high dose cytarabine. A trend towards increased toxicity was observed with the IA and IA + V arms. The use of higher dose cytarabine during induction therapy in younger patients with AML, with or without vorinostat, does not result in improved outcomes. (Funded by the US National Institutes of Health and others, ClinicalTrials.gov number, NCT01802333.).

Venetoclax and hypomethylating agent combination therapy in newly diagnosed acute myeloid leukemia: Genotype signatures for response and survival among 301 consecutive patients.

Venetoclax + hypomethylating agent (Ven-HMA) is currently the standard frontline therapy for older/unfit patients with newly diagnosed acute myeloid leukemia (ND-AML). Our objective in the current retrospective study of 301 adult patients (median age 73 years; 62% de novo) with ND-AML was to identify molecular predictors of treatment response to Ven-HMA and survival; European LeukemiaNet (ELN) genetic risk assignment was favorable 15%, intermediate 16%, and adverse 69%. Complete remission, with (CR) or without (CRi), count recovery, was documented in 182 (60%) patients. In multivariable analysis, inclusive of mutations only, "favorable" predictors of CR/CRi were NPM1 (86% vs. 56%), IDH2 (80% vs. 58%), and DDX41 (100% vs. 58%) and "unfavorable" TP53 (40% vs. 67%), FLT3-ITD (36% vs. 63%), and RUNX1 (44% vs. 64%) mutations; significance was sustained for each mutation after adjustment for age, karyotype, and therapy-related qualification. CR/CRi rates ranged from 36%, in the presence of unfavorable and absence of favorable mutation, to 91%, in the presence of favorable and absence of unfavorable mutation. At median follow-up of 8.5 months, 174 deaths and 41 allogeneic stem cell transplants (ASCT) were recorded. In multivariable analysis, risk factors for inferior survival included failure to achieve CR/CRi (HR 3.4, 95% CI 2.5-4.8), adverse karyotype (1.6, 1.1-2.6), TP53 mutation (1.6, 1.0-2.4), and absence of IDH2 mutation (2.2, 1.0-4.7); these risk factors were subsequently applied to construct an HR-weighted risk model that performed better than the ELN genetic risk model (AIC 1661 vs. 1750): low (n = 130; median survival 28.9 months), intermediate (n = 105; median 9.6 months), and high (n = 66; median 3.1 months; p < .001); survival in each risk category was significantly upgraded by ASCT. The current study identifies genotype signatures for predicting response and proposes a 3-tiered, CR/CRi-based, and genetics-enhanced survival model for AML patients receiving upfront therapy with Ven-HMA.